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clemwehner(at)sbcglobal.n
Guest

Posted: Wed Jul 11, 2007 8:12 pm Post subject: gascolator question

Does a gascolator  separate water from the fuel when fuel is flowing thru it, as the engine is  running?

  

  

 tnx,

  

 Clem  Wehner

 Lawton,  OK

 KFIV-912

    [quote][b]

Michel

Joined: 10 Jan 2006
Posts: 966
Location: Norway

Posted: Wed Jul 11, 2007 10:51 pm Post subject: gascolator question

 	  Quote: 	
		   From: clemwehner [clemwehner(at)sbcglobal.net]

 Does a gascolator separate water from the fuel when fuel is flowing thru

 it, as the engine is running?


	


It does on my marine diesel engine, Clem, where I get a lot of tank condensation. But I have never seen a drop of water in my aircraft fuel which is always in a hangar, so I wouldn't know.



Cheers,

Michel Verheughe

Norway

Kitfox 3 - Jabiru 2200

<pre><b><font size  color="#000000" face="courier new,courier">

_________________
Kitfox 3 - Jabiru 2200

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Thu Jul 12, 2007 5:36 am Post subject: gascolator question

It's supposed to.  It should be installed before the fuel pump at the lowest

point in the fuel system.  The size of the gascolator is governed by the

maximum fuel flow expected...more fuel requires a bigger gascolator.



Noel



[quote] --

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

mikeperkins

Joined: 22 May 2007
Posts: 123

Posted: Fri Jul 13, 2007 5:43 am Post subject: gascolator question

The answer to your question is yes and no. Fundamentally, a gascolator is nothing more than a “bulging low spot” in the fuel system where anything heavier than fuel can collect. Water can, and often does, collect there because water is heavier than fuel.   

Gascolators were really designed as an inexpensive fuel filter for stationary engines before filters were created. The screen inside will pass water as well as fuel. There’s no guarantee that some water won’t make it through because a gascolator is really a “static collector.”  

If the plane is sitting still and water accumulates in the tanks of a high-wing aircraft from condensation, it can “fall down” there if the conditions are right (path is open, etc). This is why it’s a good idea to leave the tank valves open. But water will accumulate in the first low spot it comes to.   

Kitfoxes have a header tank which is usually rectangular. So on the ground, the header tank has “nooks and crannies” where water can accumulate. Only the excess water that overflows from the nook or cranny can make it out of the header tank in this attitude. Also, Kitfoxes have fuel lines that typically run up hill when the aircraft sits on the ground, so water can’t get to the gascolator unless there’s a whole lot of it.   

Now start the engine. Any accumulated water in the fuel lines makes it to the gascolator. However, the water which is stuck the nooks and crannies stays in place until the aircraft is in an attitude where this water can run downhill to the gascolator. Imagine a stepped waterfall where each step has its own low spots where water can collect – when the water flow stops, these low spots still contain water. A good fuel system is one where fuel is always running downhill, even from the nooks and crannies. Most Kitfoxes aren’t made like this. Only when you tip the whole waterfall forward can the water run out of these places.   

While the engine is running, in the gascolator itself, if the turbulence is low enough, water will settle to the bottom. However, if flow rate and liquid turbulence in the bowl is great enough, water can make it through to the engine. Turbulence in the bowl can be caused by the flow itself, the vibration of the engine, and aircraft maneuvers.   

Almost all airplanes have a gascolator, yet many engines have stopped in flight because of water in the fuel.   

One more thing. If there’s any alcohol in the fuel, water will combine with it. Get some 100LL fuel. Mix fuel and water about 50:1. The water will go right to the bottom. Shake it up. The water still goes to the bottom. A gascolator can catch this water.   

But now use fuel containing ethanol and do the same thing. Strange things happen. Sometimes the water “disappears.” Sometimes the water eventually makes it to the bottom and sometimes it doesn’t. It’s really an interesting experiment to do in a test tube. With ethanol fuel, the gascolator is being called upon to do something that it wasn’t designed to do.   

Someone makes a water separator funnel you can use when fueling your airplane. I’ve heard it really works well. But then afterwards, water can condense in your tanks. The only real way to get the fuel and water to separate is to have your aircraft designed where fuel can always run downhill to the gascolator when the airplane is sitting on the ground and then not use ethanol fuels. Otherwise it’s just sheer luck.     [quote][b]

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Fri Jul 13, 2007 7:13 am Post subject: gascolator question

It was recommended to me that  after refuelling a plane take twenty minutes to have a coffee.  In that  time any water in the gas will dissipate out and can then be drained off when  the tanks are dripped before flying on.

  

 I know of at least one lake  LA-4 that crashed due to water in the fuel which was just purchased at a large  airport.  Had that pilot taken his time and dripped his tanks before taking  off he would probably still be alive today.

  

  

[img]cid:333410115(at)13072007-159A[/img]  

 Noel Loveys, RPP, AME intern

 Campbellton, Newfoundland, 

 Canada

 Kitfox Mod III-A, 582, B box, Ivo IFA

 Aerocet 1100s

 noelloveys(at)yahoo.ca (noelloveys(at)yahoo.ca)

 

 

 Do not archive

 



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_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

pwmac(at)sisna.com
Guest

Posted: Fri Jul 13, 2007 7:48 am Post subject: gascolator question

Mike,

  Great job of explaining the old school gascolator. You are totally correct in all respects.

  I would only add:

 Skystar recognized the disfunction of a tail dragger high wing with a gascolator which is why they did 3 things.

 1) Eliminated the gascolater

 2) Replaced the gascolator with an automotive final fuel filter 

 3) Started selling a proper header (or collector) tank



 The logic went just as you said when parked the water would drain to the header. So they provided a sump with quick drain in the header. I have not measured the sump volume, but rest assured it is many times the size of any gascolator. (The outlet to the engine is some distance above the bottom of the header in order to achieve this sump function).

 This design makes the quick drains in the tiny sump in the wing tanks superfluous, thus they can be eliminated.



 I understand that MurleWilliams gets the credit for urging the factory to get it correct.



 Conclusion. Copy the latest Skystar fuel system design and have a much safer plane.



 Regards, Paul

 =========================

 At 07:43 AM 7/13/2007, Perkins, Mike  wrote:



 [quote] The answer to your question is yes and no. Fundamentally, a gascolator is nothing more than a “bulging low spot” in the fuel system where anything heavier than fuel can collect. Water can, and often does, collect there because water is heavier than fuel. 



 Gascolators were really designed as an inexpensive fuel filter for stationary engines before filters were created. The screen inside will pass water as well as fuel. There’s no guarantee that some water won’t make it through because a gascolator is really a “static collector.”

 

 If the plane is sitting still and water accumulates in the tanks of a high-wing aircraft from condensation, it can “fall down” there if the conditions are right (path is open, etc). This is why it’s a good idea to leave the tank valves open. But water will accumulate in the first low spot it comes to. 

 

 Kitfoxes have a header tank which is usually rectangular. So on the ground, the header tank has “nooks and crannies” where water can accumulate. Only the excess water that overflows from the nook or cranny can make it out of the header tank in this attitude. Also, Kitfoxes have fuel lines that typically run up hill when the aircraft sits on the ground, so water can’t get to the gascolator unless there’s a whole lot of it. 

 

 Now start the engine. Any accumulated water in the fuel lines makes it to the gascolator. However, the water which is stuck the nooks and crannies stays in place until the aircraft is in an attitude where this water can run downhill to the gascolator. Imagine a stepped waterfall where each step has its own low spots where water can collect – when the water flow stops, these low spots still contain water. A good fuel system is one where fuel is always running downhill, even from the nooks and crannies. Most Kitfoxes aren’t made like this. Only when you tip the whole waterfall forward can the water run out of these places. 



 While the engine is running, in the gascolator itself, if the turbulence is low enough, water will settle to the bottom. However, if flow rate and liquid turbulence in the bowl is great enough, water can make it through to the engine. Turbulence in the bowl can be caused by the flow itself, the vibration of the engine, and aircraft maneuvers. 



 Almost all airplanes have a gascolator, yet many engines have stopped in flight because of water in the fuel. 



 One more thing. If there’s any alcohol in the fuel, water will combine with it. Get some 100LL fuel. Mix fuel and water about 50:1. The water will go right to the bottom. Shake it up. The water still goes to the bottom. A gascolator can catch this water. 

 

 But now use fuel containing ethanol and do the same thing. Strange things happen. Sometimes the water “disappears.” Sometimes the water eventually makes it to the bottom and sometimes it doesn’t. It’s really an interesting experiment to do in a test tube. With ethanol fuel, the gascolator is being called upon to do something that it wasn’t designed to do. 



 Someone makes a water separator funnel you can use when fueling your airplane. I’ve heard it really works well. But then afterwards, water can condense in your tanks. The only real way to get the fuel and water to separate is to have your aircraft designed where fuel can always run downhill to the gascolator when the airplane is sitting on the ground and then not use ethanol fuels. Otherwise it’s just sheer luck. 



 [b]

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Fri Jul 13, 2007 8:28 am Post subject: gascolator question

The gascolator on my model  III-A is definitely at the lowest point of the fuel system.  If the plane  didn't have one I'd install it.  It does separate some grit as well as  water before the fuel pump.  Installing a fuel filter before the fuel pump  is a no-no.  The only other option is the gascolator.

  

 Noel

  

  

 [quote]   

   --

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

eskflyer

Joined: 24 May 2007
Posts: 44
Location: AK

Posted: Fri Jul 13, 2007 9:02 am Post subject: Re: gascolator question

To tell people to remove the gascolator is bullshit and eliminate it totally is insane . HMMMM lets see i go from taildragger to floats and then what geee i need a gascolator . You always need one i dont care who thinks they dont . use it or loose it to drain your fuel off and get the water out . This is a no bariner one . 

My model 2 has the 9 1/2 gallon front tank and a 14 gallon wing tank . no room for a header tank in front so a gascolator is a must and even if it did have a header tank it would still have the gascolator . 

Im just going to ask . Would you be willing to go on record and sign a logbook of someones to say remove gascolator you dont need it .

_________________
FLY FUN FLY LOW FLY SLOW
John Perry
Kitfox 2 N718PD
582 cbox 2:62-1 IVO IFA
1220 Full Lotus

wingnut

Joined: 11 Jan 2006
Posts: 356

Posted: Fri Jul 13, 2007 9:37 am Post subject: Re: gascolator question

Back when I ran Mogas, I'd often get water out of my gascolator. Maybe the gascolator wasn't catching all the water but if it catches any at all then it's a good thing right? Having the gascolator doesn't hurt anything does it? I switched to 100LL six months ago and have not found water in my fuel since.

_________________
Luis Rodriguez
Model IV 1200
Rotax 912UL
Flying Weekly
Laurens, SC (34A)

clemwehner(at)sbcglobal.n
Guest

Posted: Fri Jul 13, 2007 10:57 am Post subject: gascolator question

Why is  a filter before the fuel pump a no-no?  My kit came with an in-line fuel  filter which I placed between the gascolator and the fuel pump. Is this a bad  idea?  Should the filter be before the gascolator?

  

 Thanks  for the help, I live in the middle of no-where OKlahoma where there are zero  other builders, so you guys are my only source of help. (now that John Perry  decided that Alaska was a better place to live than Oklahoma!)  

  

 Clem  Wehner

 KF-IV,  912

 Lawton, OK

 [quote]   

   --

kl7jw(at)chahtatushka.net
Guest

Posted: Fri Jul 13, 2007 11:45 am Post subject: gascolator question

One of the main  reasons there shouldn't be a fuel filter on a fuel pump input is that it's  easier to push liquid than it is to pull it.  The filter, by virtue of the  small passages thru it to allow a liquid to flow, creates a resistance to liquid  flow, thereby requiring more effective pressure to pass thru the filter.   Pumps produce pressure on the output, but not the  input.

  

 Hell,  Clem, you live in a BIG city!  I'm one that lives in the back country, at  Wilburton, OK, county seat of Latimer County, population 3000.     

  

 My dad  lives in Lawton.  I went thru high school there, then left and stayed gone  from Oklahoma for 44 years, but moved back when I decided to retire  totally.

  

 I just  bought a Kitfox IV with a Subaru engine on it.  Matter of fact, just got  home with it a couple of hours ago.

  

 John  Hart

 [quote]   --

msm_9949(at)yahoo.com
Guest

Posted: Fri Jul 13, 2007 12:07 pm Post subject: gascolator question

Good question, Clem. I have the see-thru "Purolator" type filter installed in each fuel line between wing tank and header, well ahead of the fuel pump. No flow problem experienced after 80 hours. First speck of crud in a filter and it gets removed, cleaned out. Elements changed at annual. What's wrong with that?



clemwehner <clemwehner(at)sbcglobal.net> wrote:  [quote]    Why is a filter before the fuel pump a no-no?  My kit came with an in-line fuel filter which I placed between the gascolator and the fuel pump. Is this a bad idea?  Should the filter be before the gascolator?

   

  Thanks for the help, I live in the middle of no-where OKlahoma where there are zero other builders, so you guys are my only source of help. (now that John Perry decided that Alaska was a better place to live than Oklahoma!) 

   

  Clem Wehner

  KF-IV, 912

  Lawton, OK

  [quote]  

  --

Glenn Horne

Joined: 10 Jan 2006
Posts: 96

Posted: Fri Jul 13, 2007 12:19 pm Post subject: gascolator question

Do you know any Indians in Lawton names Pacoddy. I  was in the army with an Indian

 from Lawton Ok.

 GLENN HORNE

Kitfox Model II

 [quote]   ---

clemwehner(at)sbcglobal.n
Guest

Posted: Fri Jul 13, 2007 1:01 pm Post subject: gascolator question

1.  Based on several responses, I'm thinking that there should be no  filter between the header tank and the fuel pump except for the gascolator. Is  that right?

  

 2. If  true, then should an inline filter be placed after the fuel pump enroute to  the carbs, or just not use an inline filter at all?

  

  

 John,  my wife asks what year you graduated from HS. She was from Lawton high, class of  '64 (Frances Sue Jacks).  Heck, ya'll might be cousins!

  

 tnx,

  

 Clem  Wehner

 Lawton, OK

 KFIV-912, under construction since 1991. (going for the  record!)

  

 [quote]   

   --

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Fri Jul 13, 2007 1:07 pm Post subject: gascolator question

Fuel pumps do a pretty good job  of pushing fuel but when it comes to sucking, well they suck!  Fuel filters  should be placed between the pump and the carb/fuel  injection.

  

 Slight blockage of a fuel  filter before the pump can cause your pump to airlock and the fan to stop.   Some plane have a small facet electrical pump very close to the tanks in that  case placing the filter after the electric fuel pump is  good.

  

 Noel

 [quote]   

   --

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

pwmac(at)sisna.com
Guest

Posted: Fri Jul 13, 2007 6:50 pm Post subject: gascolator question

Hey, It all depends on how your fuel system is configured. If you have wing tanks and the header behind the seat  vs a header up high behind the panel, nose gear , or floats. The fuel flow is different for each because of the flow from the tanks.  More head pressure results with the behind the seat header. Any thing that reduces the pressure to the header tanks or reduces the pressure (and subsequent flow) to the pump is a no-no. Normal design for many vehicles & planes require a filter ahead of the pump. Like when one uses a Facet.  If the pump is sensitive to particles then you need a pre filter. If not the put the filter downstream. 



  The gascolator is a filter. with a tiny sump to collect water. Do you need both a gascolator and another filter?



 If your fuel system does not have a low point drain like the recent Kitfoxes with the behind the seat header, then you need to add one and a gascolator can accomplish this function. That is why the M 2,3 with panel tank have a gascolator instead of a normal filter like the M4 etc.

 Paul

 =================

 At 12:56 PM 7/13/2007, you wrote:

 [quote]Why is a filter before the fuel pump a no-no?  My kit came with an in-line fuel filter which I placed between the gascolator and the fuel pump. Is this a bad idea?  Should the filter be before the gascolator?

  

 Thanks for the help, I live in the middle of no-where OKlahoma where there are zero other builders, so you guys are my only source of help. (now that John Perry decided that Alaska was a better place to live than Oklahoma!) 

  

 Clem Wehner

 KF-IV, 912

 Lawton, OK   --

pwmac(at)sisna.com
Guest

Posted: Fri Jul 13, 2007 7:02 pm Post subject: gascolator question

I would never advocate removing the low point drain. Like I said in my other post the latest Skystar design is the only design that removed the gascolator.



 Several owners have updated their fuel system to the low point behind the seat in the header. Think about that design and realize that it opens up other options.

 Paul

 ========================



 At 10:27 AM 7/13/2007, you wrote:

 [quote]The gascolator on my model III-A is definitely at the lowest point of the fuel system.  If the plane didn't have one I'd install it.  It does separate some grit as well as water before the fuel pump.  Installing a fuel filter before the fuel pump is a no-no.  The only other option is the gascolator.

  

 Noel

  

    --

pwmac(at)sisna.com
Guest

Posted: Fri Jul 13, 2007 7:02 pm Post subject: gascolator question

That is not a very nice message.  I guess you don't care to figure it 

out what the discussion is about.

I wonder if you read Mikes & my message.?

Paul

=======================

At 11:02 AM 7/13/2007, you wrote:

 	  Quote: 	
		  



To tell people to remove the gascolator is bullshit and eliminate it 

totally is insane . HMMMM lets see i go from taildragger to floats 

and then what geee i need a gascolator . You always need one i dont 

care who thinks they dont . use it or loose it to drain your fuel 

off and get the water out. This is a no bariner one .

My model 2 has the 9 1/2 gallon front tank and a 14 gallon wing tank 

. no room for a header tank in front so a gascolator is a must and 

even if it did have a header tank it would still have the gascolator .

Im just going to ask . Would you be willing to go on record and sign 

a logbook of someones to say remove gascolator you dont need it .



--------

FLY FUN FLY LOW FLY SLOW

John Perry

Kitfox 2 N718PD

582 cbox 2:62-1 IVO IFA

WHEELS NorthAire Floats





Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=123610#123610

pwmac(at)sisna.com
Guest

Posted: Fri Jul 13, 2007 7:02 pm Post subject: gascolator question

What I am suggesting is that there is a better way, especially for the M4 TD.

Paul

=================



At 11:37 AM 7/13/2007, you wrote:

 	  Quote: 	
		  



Back when I ran Mogas, I'd often get water out of my gascolator. 

Maybe the gascolator wasn't catching all the water but if it catches 

any at all then it's a good thing right? Having the gascolator 

doesn't hurt anything does it? I switched to 100LL six months ago 

and have not found water in my fuel since.



--------

Luis Rodriguez

Model IV 1200

Rotax 912UL

Flying Weekly

Laurens, SC (34A)





Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=123619#123619

pwmac(at)sisna.com
Guest

Posted: Fri Jul 13, 2007 7:02 pm Post subject: gascolator question

Is this an M4 with the header behind the seat? The flow restriction of a filter between the wing tank and header is not a critical as a filter after the header and before the pump. Good to have see thru filters so they cam be monitored. Filters on an M 2, 3 between the tank and header with the panel tank wound not be so good.

 Paul

 ==================



 At 02:06 PM 7/13/2007, Marco wrote:

 [quote]Good question, Clem. I have the see-thru "Purolator" type filter installed in each fuel line between wing tank and header, well ahead of the fuel pump. No flow problem experienced after 80 hours. First speck of crud in a filter and it gets removed, cleaned out. Elements changed at annual. What's wrong with that?



 clemwehner <clemwehner(at)sbcglobal.net> wrote: 

   Why is a filter before the fuel pump a no-no?  My kit came with an in-line fuel filter which I placed between the gascolator and the fuel pump. Is this a bad idea?  Should the filter be before the gascolator?

   

  Thanks for the help, I live in the middle of no-where OKlahoma where there are zero other builders, so you guys are my only source of help. (now that John Perry decided that Alaska was a better place to live than Oklahoma!) 

   

  Clem Wehner

  KF-IV, 912

  Lawton, OK

   --

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